You have to drive up to the catapult first, make sure you're still behind it or directly on it, dont be ahead of it. Put the launch bar down to extend and press U, then it should hook you up.
Thats part of the Challenge in "Challenge Campaign" gotta trust your instruments. You can increase the cockpit lighting with the 2 UV lights at the sides just below the canopy.
I think someone posted the missions in the current Press Build on this Forum earlier, there were a bunch of instant actions and I think 7 training missions IIRC
You need the 2.5 beta as the aircraft will first release there, the DCS 2.5 Requirement is there so people dont think they're gonna add it to the old 1.5.8 or older versions. But it shouldnt take too long to make it to the stable branch.